In that case you might simply pass all named args inside a hash_ref and all positional args inside an array reference. Downside of all this is of course an extreme amount of diffrently shaped brackets getting used ... 
sub get_args {
    if (scalar(@_) == 1) {
        if (ref($_[0]) eq 'HASH') {
            return "got named args!\n";
        } elsif (ref($_[0]) eq 'ARRAY') {
            return "got positional args\n";
        } else {
            die "argument wasn't a hash or array reference!\n";
        }
    } else {
        die "got more than one arg!\n";
    }
}

sub named_or_positional {
    print get_args(@_);
}
named_or_positional({foo => 'avalue' , bar => ['a', 'b']});
named_or_positional(['whatever' , 'we', 'are', 'passing']);
named_or_positional('whatever' , 'we', 'are', 'passing');

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Then you would have to check whether there is a single hash_ref or a single array_ref for determining whether it's positional or named. Any other case than a single hash or array ref would have to be considered a error.

If you don't mind the additional overhead of square/curled brackets, then it would allow you simple differentiation of named an positional args.

In reply to Re^5: Adding attributes to values? by rminner
in thread Adding attributes to values? by oyse

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